Kei my daughter really loves playing car toys . Do I encourage her to play those or I will let her play girl stuff even shes not interested ?

It depends on the age of your kid I believe. I have friends who are allowing their sons to watch Sophia and other girly cartoons. Because for them it helps the kids to understand gender equality when they grow up and not to discriminate other people when they grow up. It somehow true, when I was young I remember playing dolls with my cousins and it taught me to respect all people regardless of the gender.